As part of the program to elucidate some of the biochemical features and metabolic interrelationships of nervous system lipids, under normal and abnormal conditions, aspects of the metabolism, and insofar as feasible, the functions of glycosphingolipids are to be investigated. In particular, the involvement of these compounds in differentiation phenomena and membrane perturbation will be examined. The lipid patterns of transformed astrocytes and neuroblastoma which can be grown in cell culture will be determined and their neutral glycolipid and ganglioside composition and biosynthetic capability evaluated. Changes in pattern and metabolism of glycolipids, induced by conditions favoring the formation of new membranes or by the addition of drugs which act on the nervous system, such as tranquilizers, neurotransmitters and local anesthetics, will be investigated in intact cells, subcellular membranes and organelles of suitable clones, and brain tissue by means of double-labeled experiments.